Patrick Dempsey started a non-profit cancer center in Maine, where his mother was treated for ovarian cancer.

Dempsey told Insider that acupuncture is one of the most popular treatments offered at the Dempsey Center.

Scientific studies suggest that acupuncture can help ease the nausea and vomiting that are often side effects of radiation and chemotherapy, but it may not be the acupuncture that's making people feel better.

The mix-up can become especially pronounced when he heads home to Lewiston, Maine and visits the Dempsey Center, a complementary cancer care center that he founded in 2008, just over a decade after his mother was first diagnosed with ovarian cancer. Local patients and their families can visit for fitness, nutrition classes, counseling — all free of cost.

"Every person has a different need," Dempsey said, speaking at The Atlantic's People v Cancer conference in New York on Tuesday. "We do not treat the disease, we treat the person. We treat the whole person, the family, the caregivers, the children, everyone."

Among the cancer patients, there is one favorite treatment that rises above the rest: acupuncture.

Dempsey enjoys getting the needle treatments, too.

"I mean, everybody likes to get massage," he said.

Acupuncture — a traditional Chinese needle, heat, and pressure system that has been around for thousands of years — has been shown to relieve some of the most painful and stomach-churning side effects of cancer treatments. But while many people do feel better after an acupuncture treatment, scientists have evidence that a lot of what's going on is a placebo effect.

Patrick Dempsey leads the pack at the start of the Dempsey Challenge cycling tour in Lewiston, Maine. The event's a fundraiser for Dempsey's center, which he founded after his mother contracted ovarian cancer.
Tim Greenway/Portland Press Herald via Getty Images

Acupuncture can help cancer patients feel better, but it may not be because of the needles

Acupuncture relies on tapping specific points on the body, called "acupoints." The idea is that acupuncture can influence the body's "qi" or "chi," aka energy. Typically, treatment is done with needles that are almost as thin as a human hair, but some acupuncturists might also use heat or apply pressure.

The tradition piqued the interest of the US National Institutes of Health, where scientists started studying acupuncture in 1997. Turned out, the needling technique was effective at easing some of the nasty side effects of cancer radiation and chemotherapy, especially the nausea and severe vomiting. Acupuncture may also help patients with fatigue.

But scientists have also discovered that the benefits of acupuncture may have nothing to do with the needles or specific pressure points. Many studies which have pitted acupuncture against "sham" pricking treatments suggest there may be a powerful placebo effect at work.

"You could randomly poke somebody with toothpicks, and some studies literally do that, and that's just as effective as doing all the things that an acupuncturist is supposed to do," Dr Steven Novella, a neurologist at Yale, previously told Business Insider.

Whatever the mechanism, Dempsey said he sees notable changes when patients try acupuncture at his cancer center.

"It's nice to see when people are hesitant at the beginning, and then they try it, and they're a few sessions in, and they notice a difference," he said. "Then they're like, 'Ahh, yeah.'"